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This document explains which countries and agencies participate in the development of Space Station Freedom, what the different structures on the station will be, and who is responsible for constructing them. The systems which will be operational in the baseline configuration of the station are listed, as is its assembly schedule. An overview of plans for space station evolution is also given.
Understanding and forecasting the intricate freight mode choice behavior under various industry, policy, and technology contexts is essential in freight planning and policymaking. Numerous models have been developed in prior studies to provide insights into freight mode selection, the majority of which use discrete choice models such as multinomial logit (MNL) models. However, logit models often rely on linear specifications of independent variables, despite potential nonlinear relationships in the data. Moreover, there often lacks a heuristic and efficient approach to identify such complex relationships to define the logit model specifications. To fill this gap, we developed an MNL model for freight mode choice using the insights from state-of-the- art machine learning (ML) models. ML models can capture the nonlinear nature of the complex decision-making process, and recent advances in 'explainable AI' have greatly improved their interpretability. The interpretable ML methods help enhance the performance of MNL models and advance knowledge of freight mode choice. Specifically, the influential factors and their relationship with individual modes are identified using SHapley Additive exPlanations (SHAP) to improve the MNL's performance. The workflow is demonstrated in a case study of Austin, Texas, and the SHAP results reveal multiple nonlinear relationships predicted by ML models. Incorporating those relationships into MNL model specifications improves the interpretability and accuracy of the MNL model compared to a conventional MNL model. Findings from this study can be used to guide freight planning and inform policymakers and practitioners on how key factors affect freight decision-making.
NASA's plans for the Space Shuttle tracking and data acquisition system are described. The limitations of the techniques now used for tracking and data acquisition support of earth orbiting spacecraft are discussed. NASA's solution to these limitations, the Tracking and Data Relay Satellite System, is described. The system's geometrical coverage and technical characteristics are explained. Operation of the system for Space Shuttle support is described in overview terms.
The development of the Shuttle Transportation System (STS) by the United States and the Spacelab pressurized modules and pallets by the European Space Agency (ESA) presents a unique multi-mission space experimentation capability to scientists and researchers of all disciplines. This capability is especially pertinent to life scientists involved in all areas of biological and behavioral research. This paper explains the solicitation, evaluation, and selection process involved in establishing life sciences experiment payloads. Explanations relative to experiment hardware development, experiment support hardware (CORE) concepts, hardware integration and test, and concepts of direct Principal Investigator involvement in the missions are presented as they are being accomplished for the first Spacelab mission. Additionally, discussions of future plans for life sciences dedicated Spacelab missions are included in an attempt to define projected capabilities for space research in the 1980s utilizing the STS.
The first of two demonstration flights of the tethered satellite system (TSS) is planned for the STS-52 flight and is designed to study tether electromagnetic interaction. The magnetospheric-ionospheric-atmospheric coupling processes in the lower troposphere are to be directly measured on the second TSS mission. An operational overview of the TSS-to-orbiter-to-ground interface is given and the TSS deployment concept is explained. Other aspects discussed include the tethered satellite-to-orbiter interface; tether control mechanisms; tether materials, and electrical interfaces. The design of the demonstration flight satellite and its instruments is described. The capabilities of the TSS for the demonstration flight are listed.
A dynamic world model is presented on which all planning, sensing, and control functions are based. A planning system that specifies how task are to be performed and the method used for sensing the state of the task are presented. The objectives of the control law and the algorithm used in the controller are given. Practical considerations are addressed, and some important details, such as the use of the null task, are explained. An example task of opening a door is examined.
This study is aimed at enhancing the understanding of turbulent premixed methane-air combustion. Such understanding is essential since: (1) many industries are now pursuing lighter hydrocarbon alternative fuels and the use of premixed flames to reduce pollutant emissions, and (2) the characteristic dimensions and flow rates of most industrial combustors are often large for flows to be turbulent. The specific objectives of the study are: (1) to establish the effects of process variables (e.g., flow rate, fuel/air ratio, chlorinated hydro-carbons, and pressure) on the emissions and flow structure (velocity distribution, streamlines, vorticity and flame shape), and (2) to develop a mechanistic model to explain the observed trends. This includes the acquisition of Dantec FlowMap Particle Image Velocimeter. The design and fabrication of the premixed burner has also been completed. The study is now at the stage of testing of equipment and analytical instruments. The presentation will give details on the tasks completed and on the current and future plans. The project is progressing well and all activities are on schedule. The outlook for the success of the project is bright.
The Facilities Engineering and Architectural Branch is responsible for the design and maintenance of buildings, laboratories, and civil structures. In order to improve efficiency and quality, the FEAB has dedicated itself to establishing a data infrastructure based on Geographic Information Systems, GIS. The value of GIS was explained in an article dating back to 1980 entitled "Need for a Multipurpose Cadastre" which stated, "There is a critical need for a better land-information system in the United States to improve land-conveyance procedures, furnish a basis for equitable taxation, and provide much-needed information for resource management and environmental planning." Scientists and engineers both point to GIS as the solution. What is GIS? According to most text books, Geographic Information Systems is a class of software that stores, manages, and analyzes mapable features on, above, or below the surface of the earth. GIS software is basically database management software to the management of spatial data and information. Simply put, Geographic Information Systems manage, analyze, chart, graph, and map spatial information. GIS can be broken down into two main categories, urban GIS and natural resource GIS. Further still, natural resource GIS can be broken down into six sub-categories, agriculture, forestry, wildlife, catchment management, archaeology, and geology/mining. Agriculture GIS has several applications, such as agricultural capability analysis, land conservation, market analysis, or whole farming planning. Forestry GIs can be used for timber assessment and management, harvest scheduling and planning, environmental impact assessment, and pest management. GIS when used in wildlife applications enables the user to assess and manage habitats, identify and track endangered and rare species, and monitor impact assessment.
The Facilities Engineering and Architectural Branch is responsible for the design and maintenance of buildings, laboratories, and civil structures. In order to improve efficiency and quality, the FEAB has dedicated itself to establishing a data infrastructure based on Geographic Information Systems, GIs. The value of GIS was explained in an article dating back to 1980 entitled "Need for a Multipurpose Cadastre which stated, "There is a critical need for a better land-information system in the United States to improve land-conveyance procedures, furnish a basis for equitable taxation, and provide much-needed information for resource management and environmental planning." Scientists and engineers both point to GIS as the solution. What is GIS? According to most text books, Geographic Information Systems is a class of software that stores, manages, and analyzes mapable features on, above, or below the surface of the earth. GIS software is basically database management software to the management of spatial data and information. Simply put, Geographic Information Systems manage, analyze, chart, graph, and map spatial information. At the outset, I was given goals and expectations from my branch and from my mentor with regards to the further implementation of GIs. Those goals are as follows: (1) Continue the development of GIS for the underground structures. (2) Extract and export annotated data from AutoCAD drawing files and construct a database (to serve as a prototype for future work). (3) Examine existing underground record drawings to determine existing and non-existing underground tanks. Once this data was collected and analyzed, I set out on the task of creating a user-friendly database that could be assessed by all members of the branch. It was important that the database be built using programs that most employees already possess, ruling out most AutoCAD-based viewers. Therefore, I set out to create an Access database that translated onto the web using Internet Explorer as the foundation. After some programming, it was possible to view AutoCAD files and other GIS-related applications on Internet Explorer, while providing the user with a variety of editing commands and setting options. I was also given the task of launching a divisional website using Macromedia Flash and other web- development programs.
Now that the International Space Station is undergoing assembly, NASA is strategizing about the next logical exploration strategy for robotic missions and the next destination for humans. NASA's current efforts are in developing technologies that will both aid the robotic exploration strategy and make human flight to other celestial bodies both safe and affordable. One of these enabling technologies for future robotic and human exploration missions is aeroassist. This paper will (1) define aeroassist, (2) explain the benefits and uses of aeroassist, and (3) describe a method, currently used by the NASA Aeroassist Working Group, by which widely geographically distributed teams can assemble, present, use, and archive technology information.
Port electrification can take many forms, such as electrifying cargo handling equipment or deploying a microgrid to power critical port infrastructure. To help evaluate the growing challenge of increased electrification and its impacts on the system, the U.S. Department of Energy, Office of Electricity’s Microgrids R&D [research and development] program created this Port Electrification Handbook through a project led by Pacific Northwest National Laboratory. The goals of this handbook are the following: help port operators and planners evaluate different electrification technologies, explain how these technologies could aid and impact ports and surrounding communities, provide step-by-step considerations for port electrification.
Thin-metal foils are used in intense relativistic beam experiments for various purposes. In planning these experiments and analyzing the results it is often desirable to have an estimate of the temperature reached during the beam pulse. This can be deduced from an estimate of the energy deposited by the beam, and the specific heat capacity of the material, which depends on the temperature. The methodology for doing this is explained herein, and a metric for foil survivability under heating by an intense relativistic electron beam is suggested.
This paper looks at the Independent Verification and Validation (IV&V) of NASA's Space Shuttle Day of Launch I-Load Update (DoLILU) project. IV&V is defined. The system's development life cycle is explained. Data collection and analysis are described. DoLILU Issue Tracking Reports (DITRs) authored by IV&V personnel are analyzed to determine the effectiveness of IV&V in finding errors before the code, testing, and integration phase of the software development life cycle. The study's findings are reported along with the limitations of the study and planned future research.
Magellan radar data of Venus reveal 163 large radial lineament systems composed of graben, fissure, and fracture elements. On the basis of their structure, plan view geometry, and volcanic associations, at least 72% are interpreted to have formed primarily through subsurface dike swarm emplacement, the remainder through uplift or a combination of these two mechanisms. The population of swarms is used to determine regional and global stress orientation. The stress configuration recorded from 330-210 deg E (Aphrodite Terra) is best explained by isostatic compensation of existing long wavelength topography or coupling between mantle flow and the lithosphere. The rest are correlated with concentrations of rifting and volcanism in the Beta-Atla-Themis region. The global stress field on Venus is different than that of Earth, where plate boundary forces dominate.
This Commissioning Guidance for Energy Savings Performance Contracts (ESPCs) is DOE’s official guidance for ordering agencies under the current DOE ESPC IDIQ contract. This guidance document explains how commissioning of energy conservation measures (ECMs) and water conservation measures (WCMs) is incorporated into the ESPC process, roles and responsibilities in project commissioning, and key elements of commissioning. This document updates the previous version, released in 2015. This guidance can also be used as applicable in the development of ESPC ENABLE and UESC performance assurance plans.
Paul Hill, STS 114 Lead Shuttle Flight Director, David Wolf, Extravehicular Activity (EVA) Branch Chief, JSC from the Astronaut Office, and Kelly Beck, STS-114 Team 4 Flight Director are seen on the 8th day of the Space Shuttle Discovery Mission. Paul Hill presents and explains charts of the Gap Fillers that Steve Robinson will be pulling off during his EVA. The charts include: 1) Protruding Gap Fillers; 2) Starboard Worksite Access; 3) Protruding Chine Gap Filler; 4) Port Gap Filler Space Shuttle Remote Manipulator System (SSRMS) Position; and 5) Port Gap Filler Close-up View. Kelly Beck talks about how the plan for the gap fillers were arranged, and presents the tools and techniques that Steve Robinson will be using during the EVA. David Wolf demonstrates how the EVA will be performed using forceps and a hacksaw to remove the gap fillers. The presentation ends with a question and answer period from the news media.
The Inflation Reduction Act introduced or expanded a suite of federal tax credits for clean electricity generation and customer adoption of electric (and other highly efficient) end-use equipment. These incentives are expected to drive changes in both the electricity generation mix and demand for electricity (especially for space heating and light-duty vehicles), which are highly interconnected. In this session, Caitlin Murphy, Group Manager and Senior Analyst in NREL's Strategic Energy Analysis Center, will present findings from her team's recent state-level analysis on the combined effects of various IRA incentives on customer expenditures for electricity, natural gas, and gasoline. She will present and explain the regional variations observed in their analysis, based on interactions between end-use equipment cost and performance and projections for future energy prices.
Shuttle mission plans recently developed by NASA for the time period 1980-1991 are presented. Standard and optional services, which will be available to users of the Space Transportation System (STS) when it becomes operational in the 1980's, are described. Pricing policies established by NASA to encourage use of the STS by commercial, foreign and other U.S. Government users are explained. The small Self-Contained Payload Program, which will make space flight opportunities available to private citizens and individual experimenters who wish to use the Space Shuttle for investigative research, is discussed.